The genus Nairovirus (family Bunyaviridae) contains seven serogroups consisting of 37 predominantly tick-borne viruses, including several associated with severe human and livestock disease such as Crimean-Congo haemorrhagic fever (CCHF) and Nairobi sheep disease (NSD) viruses respectively. The genome of the nairoviruses consists of three negative-sense single-stranded RNA segments, small (S), medium (M) and large (L) that encode the nucleocapsid protein, glycoproteins (Gn and Gc) and viral polymerase respectively. Little genetic data exists for this genus of trisegmented viruses, with full genome sequences available in GenBank for only nine viruses, most of which belong to the CCHF and NSD serogroups.
Nairoviruses have rarely been isolated in Australia or its territories. The isolation of three nairoviruses has previously been documented; two Sakhalin serogroup viruses (Taggert (TAGV) and Finch Creek viruses) isolated from Macquarie Island 1500km SSE of Tasmania, and a Dera Ghazi Khan serogroup virus (NT15470) isolated in the Northern Territory. We utilised Illumina sequencing technology to sequence the near-complete genomes of TAGV and an additional virus, Vinegar Hill virus (VINHV) isolated in Queensland decades ago. Here we present the subsequent characterisation and phylogenetic analysis of these two viruses. Our results show that TAGV is related to other Sakhalin group viruses, as expected, whilst VINHV is related to viruses of the Dera Ghazi Khan serogroup. This is the first time that near-complete genomes have been reported for viruses of the Sakhalin or Dera Ghazi Khan serogroups.